In general, various shapes of banners are placed along streets in the transverse or longitudinal direction with commercial advertisements or event announcements printed thereon.
In the case of a banner placed in the longitudinal direction, it is customary to position a support in the vertical direction and install a pair of transverse rods along the longitudinal direction of the support in such a manner that the rods are spaced a distance corresponding to the longitudinal length of the banner. The top and bottom of the banner engage with the transverse rods so as to be fixed thereto, respectively. To this end, the banner has support frames placed at its top and bottom, respectively. The support frames extend as much as the transverse length of the banner.
However, this type of banner has a problem in that fixation of the top and bottom of the banner to the transverse rods is unreliable, because the fixation simply depends on engagement between the support frames, which are placed on the top and bottom of the banner, and the transverse rods.
As a result, the banner easily detaches from the support due to strong wind, for example, and flaps in the wind. This increases safety concerns, adversely affects the merits of advertisements or announcements, and degrades the aesthetic view of streets.
Furthermore, the fact that a separate support must be fixed to the ground restricts the selection of installation place and costs a large amount of money. In an attempt to solve these problems, a banner stand, which needs no separate support, has been proposed. For example, Korean Registered Patent No. 487,697 discloses a fixed stand, which will now be described briefly.
The fixed stand includes a body fixed to a to-be-mounted object, the body having a plurality of pole connectors formed along the outer surface at an interval, as well as a bolt through-hole, through which a mounting bolt extends; a mounting member directly mounted on the to-be-mounted object so as to fix the body to the object, the mounting member having a mounting bolt formed thereon so as to extend through the bolt through-hole; a plurality of poles having one side removably mounted on the pole connectors of the body with the other side engaging with a to-be-supported object; and a female screw screw-coupled to the leading end of the mounting bolt, which extends through the bolt through-hole of the body and protrudes from the front surface of the body, so that the body is fixed to the mounting member.
For installation of the fixed stand, the mounting member is firmly fixed to a to-be-mounted object (e.g. wall surface) by a number of screws. After coupling the poles to the body with a to-be-supported object (e.g. banner) supported on the poles, the body is fixed to the mounting bolt of the mounting member by the female screw.
However, the fixed stand has a problem in that its installation involves complicated and inconvenient procedures. Particularly, mounting holes must be made on the wall surface in order to fix the body. After initially fixing the mounting member to the mounting holes with a number of screws, the female screw is coupled to the mounting bolt. When the stand is to be removed, the female screw is unfastened from the mounting bolt, and the screws are unfastened so that the mounting member is released.
Therefore, although the fixed stand may pose no problem when it remains fixed for a long period of time, it is not suited to frequent installation and removal. In addition, the mounting holes remain on the wall surface even after removal of the stand and adversely affect the interior of the building.
In order to avoid these problems, a device adapted for easy mounting and removal has been proposed, as that disclosed in Japanese Patent Publication No. 2001-220783 entitled ROTATABLE SUCTION DEVICE FOR SHOWER HOSE RETAINER, which will now be described briefly.
The rotatable suction device includes a bowl-shaped suction plate made of an elastic material so that it can adhere to a wall surface and a retainer body having a base positioned on the outer peripheral edge of the upper surface of the suction plate so that it can be bonded thereto and an operation unit positioned so as to be operated and rotated relative to the base. A shower hose retainer is positioned between the operation unit and the base outside of the base. Suction force is generated by rotating the operation unit and lifting the suction plate in a direction perpendicular to the wall surface while the base is bonded to the outer peripheral edge of the upper surface of the suction plate.
Particularly, the rotatable suction device has a bolt integrally formed at the center of the upper surface of the suction plate. The operation unit is rotated while an end of the bolt protrudes through a through-hole of the operation unit and remains fixedly supported by a nut. As a result, the bolt is lifted in a direction perpendicular to the wall surface, and so is the suction plate, thereby generating suction force.
However, the rotatable suction device has a problem in that, when the operation unit is rotated, external force acts on the suction plate and tends to rotate it together with the operation unit. This causes the suction plate to slip on the wall surface. Such a slip adversely affects the suction force between the wall surface and the suction plate.
The suction place exerts maximum suction force when its center is pulled to the greatest extent while its bottom surface initially remains flat. However, the fact that the bolt at the center of the suction plate is used to fix the end, which protrudes upwards from the through-hole of the operation unit, with the nut makes it difficult to maintain the bottom surface of the suction plate in an initially flat condition before the suction plate is operated.
This means that, when the bottom surface of the suction plate is not flat after the nut is coupled to the bolt, the suction force exerted by the suction plate decreases seriously.
Furthermore, as the operation repeats rotation for compression and inverse rotation towards original position, the nut is gradually unfastened from the bolt. This weakens the suction force of the rotatable suction device little by little.
As another approach for easy mounting and removal of a banner, Korean Registered Utility Model 20-216370 entitled REMOVAL FLAGPOLE FIXING APPARATUS discloses a device adapted for easy mounting and removal, which will now be described briefly.
The removable flagpole fixing apparatus includes a rotatable flagpole having a screw and a rotatable ball formed on the upper and lower ends thereof, respectively; a flagpole support having a recess formed on the inner wall surface of an opening of its bottom surface and a flagpole insertion hole formed on the upper surface so that the screw of the rotatable flagpole is inserted therein and the rotatable ball engages therewith in order to prevent it from escaping; a clip portion inserted into the flagpole support and fixed thereto, the clip portion having a ball support recess formed on its upper surface so that the rotatable ball is seated thereon, the clip portion having a step formed along the inner wall surface of the opening on the bottom surface so that a button attached to an object engages therewith, the clip portion having a protrusion formed along its outer peripheral surface so as to fit into the recess of the flagpole support, the clip portion being folded along a seam on the outer peripheral surface so as to be bifurcated; and a flag rod having an insert coupler integrally formed therein so that the screw of the rotatable flagpole is fastened thereto.
After the rotatable flagpole is inserted into the flagpole insertion hole of the flagpole support, the clip portion is inserted from behind the flagpole support so that the top surface of the clip portion compresses the bottom surface of the rotatable ball of the rotatable flagpole.
The removable flagpole fixing apparatus has a problem in that, whenever the rotatable flagpole is separated from the flagpole support, the clip portion must be separated from the flagpole support in advance.
This means that, unless the clip portion is separated from the flagpole support, the rotatable flagpole can be neither separated from the upper surface of the flagpole support nor mounted therein.
For easy mounting/removal of the protrusion of the clip portion onto/from the recess of the flagpole support, the flagpole and the clip portion must have at least a predetermined size. This is because the mounting/removal of the protrusion is based on elastic deformation of the lateral wall of the flagpole support within a predetermined range.
Such a requirement on the size of the flagpole support and the clip portion inevitably weakens the gripping force of the rotatable flagpole, which is supported between the flagpole support and the clip portion. This has a problem in that, when the rotatable flagpole is slanted at an angle, it is difficult to maintain the slanted condition for a long period of time.